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ITER NEWSLINE 235
The ITER cryostat will be the world's largest high-vacuum pressure chamber. On 17 August, the contract for the manufacturing of the 3,800 tonne steel-structure was signed with the Indian company Larsen & Toubro (L&T) Ltd.
The cryostat forms the vacuum-tight container surrounding the ITER vacuum vessel and the superconducting magnets and acts essentially as a very large refrigerator. It will be made of stainless steel with thicknesses ranging from 50 mm to 250 mm. The structure will have to withstand a vacuum pressure of 1 x 10 -4 Pa; the pump volume is designed for 8,500 m³. Its overall dimensions will be 29.4 metres in diameter and 29 metres in height. The heavyweight will weigh in at more than 3,800 tonnes, making it the largest vacuum vessel ever built out of stainless steel.
The cryostat will have 23 penetrations to allow internal access for maintenance as well as over 200 penetrations—some as large as four metres in size—providing access to the vacuum vessel for cooling systems, magnet feeders, auxiliary heating, diagnostics, and the removal of blanket sections and parts of the divertor. Large bellows will be used between the cryostat and the vacuum vessel to allow for thermal contraction and expansion in the structures.
India, being one of the seven Members of the ITER project, is in charge of procuring the cryostat. On 17 August Shishir Deshpande, project director of ITER-India and Anil Parab, vice president of the L&T Heavy Engineering division, signed the contract for the manufacturing of the ITER cryostat.
The design of the ITER cryostat represented a huge international endeavour involving engineers and technicians from both the ITER Organization and the Indian Domestic Agency. "The cryostat is an essential part of the ITER machine. Seeing this huge component taking shape in the factory is certainly important and encouraging news. It means that the ITER project has entered a decisive phase," ITER Director-General Osamu Motojima said.
The cryostat will be manufactured by the Heavy Engineering division of L&T at its Hazira plant, near Surat, Western India in the state of Gujarat. It will be dispatched in 54 modules to the ITER site in Cadarache, as it cannot be transported in its entire size. The cryostat modules will be pre-assembled in a temporary workshop at the ITER site and then transported to the Tokamak Pit, where they will be welded together by using the advanced "narrow groove all position gas tungsten arc welding technique."
Mr. M.V. Kotwal, member of L&T Board and president of L&T Heavy Engineering, stated: "L&T is proud to be part of this mammoth global collaborative research to build a greener planet."
Recently, the standard ITER CODAC (Control, Data Access and Communication) technologies successfully demonstrated their adaptability and operability for tokamak control at the Korea Superconducting Tokamak Advanced Research (KSTAR), in operation since 2008.
Like ITER CODAC, the KSTAR control system uses EPICS as middleware for tokamak control and operation. Therefore, KSTAR is a natural target for evaluating and validating CODAC technologies as has been identified in the Memorandum of Understanding between ITER Organization and National Fusion Research Institute (NFRI).
During the last 15 months, the KSTAR control team has implemented a duplication of the fuel control system and a part of the plasma control system using CODAC technologies (standardized hardware and CODAC Core System). On 26 July, a first test was successfully executed by injecting deuterium gas into the vacuum vessel based on pre-configured waveforms from the plasma control system.
The project will be completed in November by using real density signals from a millimetre-wave interferometer and closing the density feedback control loop during the KSTAR plasma operation.
The KSTAR fuelling system operates with four different gases for plasma creation, wall cleaning and diagnostics. For the experiment, one piezo-electric valve (for deuterium gas) was selected as an actuator. Various pre-configured patterns were used as reference inputs to the plasma control system for controlling the fuel injection. The plasma control system was implemented on a high performance computer using ATCA form factor, CODAC standard real-time operating system (MRG-R) and MARTe real-time framework originally developed at JET.
The density signal was simulated by programmable waveforms. A CODAC standard fast controller (fuel controller) was also implemented to control the embedded piezo-valve controller and to acquire diagnostics signals such as vacuum vessel pressure, gas flow, valve drive voltage, etc. at 10 kHz. The plasma control system communicated with the fuel controller over the standard CODAC real time network at 1 kHz.
As the measurements from the first test showed identical results as the KSTAR fuelling system, it was confirmed that the technologies adopted or being considered for ITER CODAC were applicable for the plant control at tokamak, that is, CODAC is heading in the right direction.
Light is the etching tool industry uses to create the microscopic circuits on the surface of silicon microprocessors. As "chips" follow Moore's law and become more powerful with each new generation, the features on the silicon become denser, meaning smaller structures need to be etched.
The short-wave (193 nanometres) ultraviolet light that is currently used by the industry is neither "sharp" nor powerful enough to meet the next generations' standards. What industry needs is light with an even shorter wavelength—less than one-tenth the present one—that will enable the etching of even finer grooves.
Such extreme ultraviolet light can be created only from plasmas. Scientists at the University of Washington College of Engineering have developed a "low-cost version of a fusion reactor," dubbed ZaP, that should provide the light output that the microprocessor industry needs.
Read the full story here
Everything was "special" last week as the ITER Management Advisory Committee (MAC) met for two days in Cadarache in response to the request formulated by the ITER Council last June at its 10th meeting in Washington D.C.
This Special MAC Meeting, with a limited number of participants, aimed at monitoring the implementation of the ITER schedule recovery plans and at reviewing the actions already implemented (or to be implemented in the near future) by the ITER Organization.
Also special was the fact that the heads of the seven Domestic Agencies, or their representatives, instead of being seated among the MAC members as they usually are at MAC meetings, were seated among the ITER Organization management. This small change in seating arrangements conveyed a strong meaning: Domestic Agency heads and ITER Organization management now form what Director-General Motojima terms the "Unique ITER Team," an integrated body pursuing a common goal and resolutely pulling in the same direction.
Considering the importance of the issues discussed, ITER management also decided to convene an all-staff meeting in the afternoon following the conclusion of the MAC special session, and asked both MAC Chair Ranjay Sharan (India) and ITER Council Vice Chair Edmund Synakowski (US) to address the assembled ITER personnel.
Speaking to a packed audience, Ranjay Sharan, whom Director-General Motojima introduced as "one of the first MAC members" and one who had seen "all the ups and downs of the project since 2007," said that the present moment was definitely more "up" than "down." "MAC," he said, "is very pleased to see that recovery actions are now in place [...] The issues, constraints and restraints are now identified and I have no doubt you will solve them [...] In the past three months, you have achieved one more milestone than the target—this is a very good signal!"
A long-standing "member of the family of fusion" and the present Associate Director (Office of Science) for Fusion Energy Sciences at the US Department of Energy, Edmund Synakowski gave a very moving speech, telling the assembled staff that they were "at the ground floor of something truly historic" and confessing that he was "both impressed and envious" at the challenge being raised here at Cadarache. "We all recognize," he said, "the excellence presently executed in the ITER Project."
Kijung Jung, head of ITER Korea, conveyed on behalf of all Domestic Agencies the "common appreciation for the great efforts that are being accomplished" and assured that "all Domestic Agencies will do their best for the ITER Project. Let's go toward success together!" he cheered.
Spirits were high when Osamu Motojima took the floor to present the details of the recovery plans and corrective actions being implemented. "Cost is contained; slippage is being recovered," he said. "The ITER train is back on track; now we need to accelerate." He stressed that the progress gained and noted by this MAC are due to contributions of the staff and, he insisted, "that this is each and every one of you."
Schedule Control; a Simplified Integration Scheme; more integration between the ITER Organization and Domestic Agencies ("all the way to the Technical Responsible Officers"); and the acceptance that "building designs should be frozen as soon as possible" are some of the actions and attitudes that will contribute to the acceleration.
Director of the Department for ITER Project Rem Haange then provided further details on the status of the "critical and super critical items" such as building construction; vacuum vessel; toroidal field, polodial field and central solenoid coils; and the cryostat. "We have introduced methods to understand the slippages and to stop them," he explained.
In his address, Director-General Motojima evoked the figure of the ancient Greek historian Herodotus who regretted in his time (5th century B.C.) that "each physician was the physician of one disease and of no more," and that physicians who could treat the whole body were impossible to find.
Replace "physicians" with "engineers and physicists," the Director-General suggested and—at a distance of 25 centuries—you can draw a parallel with the present situation. "We all need to have a broader view. We all need to understand the person who is near us," said DG Motojima.
This is the only way to treat the whole body and to build the whole machine.
Pictures of Special MAC Meeting can be viewed here.
The ITER Organization and the Ministry of Science and Technology (MOST) of the People's Republic of China have signed a Memorandum of Understanding aiming to promote scientific and technological cooperation between the world-spanning network of laboratories and institutes engaged in fusion research.
On 13 August, during his recent visit to Beijing, ITER Director-General Osamu Motojima and Vice-Minister CAO Jianlin signed the Memorandum. China is one of the seven founding Members of the ITER Organization; MOST steers the country's national scientific and technological development.
The agreement comprises "the exchange of and training of scientists, engineers, specialists, administrators and project managers with regard to mega-science projects for agreed periods of time; the organization of seminars and workshops; and the exchange of information and data on scientific and technical activities taking into account the Intellectual Property rules of the ITER Project."
Work kept progressing on the ITER platform during the summer recess.
Blinding concrete was poured over the rock surface of the future Assembly Hall adjacent to the Tokamak Seismic Pit. The resulting clean and flat 6,000 m² surface will be used as a working platform to install the reinforcement steel of the building's structural foundation.
In parallel, workers finalized rock excavation for the galleries that will run in the foundations. In the picture, an excavator is at work on an 8 x 7 metre gallery that will serve as an entry point for most of the electrical cables providing energy to the tools and devices to be used for assembly operations.
Work began on the networks of Contractor Area #2 and continued throughout the platform as manholes connecting the large 1.6-kilometre-long concrete piping of the underground drainage network were installed.
Foundation work on the Assembly Hall worksite will extend into March 2013, and drainage network installation should be completed by November of this year.